Improvement in devices for unlocking locked nuts



N M. McDEvlTT. Devices for Unlcking Locked Nuts. No.149,773. V Patented April14,1874.

e l. www@ e xg nvenjror 1I NITED STATES ATRT OFFICE..

MARTIN MOnRvITT, or HAMPTON, vIRGINIA.

IMPROVEMENT IN DEVICES FOR UNLOCKING LOCKED NUTS.

Specification forming part of Letters Patent No. 149,773., dated April 14, 1874; application filed July 9, 1873.

To ali whom it may concern:

Be it known that I, MARTIN MoDEvITT, of Hampton, in the county of Elizabeth City and State of Virginia, have invented certain new and useful Improvements in Unlocking Lock-Nuts; 'and I'do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this speciiication.

My invention relates to a new and improved device to be used in connection with a locknut when applied to the ordinary bolt, for unlookin g the same in order to remove said nut 5 and it consists of a metallic thimble with slotted sides arranged to t over the end of the bolt, the-lower edge resting upon a shoulder on the lower half of the lock-nut, which is made in two part-s with locking-faces, as will be hereinafter described, in such a manner tha-t the lower part of said nut may be pressed away from the upper part by means of a screwnut on the bolt which bears against the upper end of the thimble, thus separating the locking-faces of the two parts of the nut, and allowing the upper part to be turned until both parts can be removed.

Figure l represents a view of the face of the lower portion of the lock-nut; Fig. 2, a view of the face of the upper portion of the same; Fig. 3, a sectional view of the nut and bolt with the unlocking device applied; Fig. 4, a

perspective view of lthe metallic thimble5.

Fig. 5, a perspective view of the lower portion of the nut; and Fig. 6, a perspective view of the upper portion of the same.

The nut is formed in two parts, A B, as slrown, both parts being provided on their locking-faces, which are placed together when' i the nut is in position, with a series of lockingshoulders, a a and c c. The lower portion of said nut is provided with a rectangular aperture, d, through center, which fits over the rectangular portion ofthe bolt F below the screw-thread. The upper portion B is provided with a circular aperture through its center, in which a screw-thread is cut,for1n ing a female screw to fit the threads of the male screw on the bolt. Below the lower portion of the lock-nut B is placed a circular elastic washer, C, which rests against the side of the object to be secured by the bolt.

It will be seen that when the bolt is in place, and the washer C and partA of the lock-nut are in place, the part B may be screwed down upon the partA until the faces meet, and, by farther turning the upper part B, the elastic cushion or washer C will give, allowing the locking-faces of the parts A and B to engage, whereby the upper one becomes fastened, and cannot be turned on the screw to loosen the lower part.

In order to unlock the nut thus secured, I employ a metallic thimble, D, with slotted sides, as shown, and a circular aperture through the top. This thimble is so construoted as to t over the end of the bolt and the lock-nut thereon, as shown in Fig. 3, and rest against a shoulder, c, upon the lower portion A of the locknut.

The aperture through the top of the thimble may be provided with a screw-thread to fit the threads of the screw on the bolt, or it may be left plain, and a screw-nut, E, ma)T be applied to the bolt over said thimble.

The object of this arrangement is to allow the lower edge of the thimble to b e made to bear against the lower portion A of the locknut, in order-to separate the two portions or unlock the nut.

It will be evident that, by causing the thimble to bear against the lower portion of the lock-nut A, the said portion will be pressed against the yielding cushion C, and the locking-faces of the two parts separated. The upper portion B may then be unscrewed a suiiicient distance to prevent the two faces from meeting, when the thimble is removed by means of the fingers or a wrench, which may applied to the nut through the slots in the thimble. The thiinble may then be removed, after which the nut may be taken entirely 0E the bolt.

In combination with the shouldered washer A and elastic washer C, the thimble D and nut E, for the purposes specified.

In testimony that Iclaim the foregoing I have hereunto set my hand this 30th day of May, 1873.

MARTIN MoDEVITT.

l/Vitnesses:

W. H. GLEAsoN, J A.Mns H. MANDEVILLE. 

